Crop dryer



June 5, 1962 E. w. EPPERSON 3,037,297

CROP DRYER Filed June 12. 1958 2 Sheets-Sheet l 24 as v v /a Earl W. Epperson 1N VENTOR.

June 5, 1962 E. w. EPPERSON 3,037,297

' CROP DRYER Filed June 12, 1958 2 Sheets-Sheet 2 Fig.2 Fig.3

Earl W. Epperson,

INVENTOR.

BY v

3,037,297 (IROP DRYER Earl W. Epperson, Sumner, Iowa Filed June 12, 1958, Ser. No. 741,577 4 Claims. (Cl. 34-102) This invention comprises a novel and useful crop dryer and more particularly relates to an apparatus for effecting an improved and efiicient drying of crops or granular materials during the fiow by gravity of the same through the device.

A further object of the invention is to provide a dryer whereby the granular or other matter being dried will during a free fall through the device be subjected to at least two passages of a heated drying air therethrough.

A further object of the invention is to provide an apparatus in accordance with the preceding objects wherein the material being dried may be caused to repeatedly circulate through the device for successive drying operations thereon if desired.

Still another object of the invention is to provide an apparatus according to the foregoing objects wherein the rate of flow of the material being dried from the device may be controlled or regulated thereby further controlling the efliectiveness and efficiency of the drying operation in the apparatus.

A still further important object of the invention is to provide a dryer of the gravity operated type wherein the material being dried is caused to fall by gravity in counter-flow to an upwardly rising stream of heated air constituting the drying medium; and whereby this heated air is caused to thoroughly and uniformly permeate and penetrate in at least two successive operations the falling material to be dried thereby.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

FIGURE 1 is a side elevational view, parts being broken away, showing a suitable form of drying apparatus in accordance with the principles of this invention;

FIGURE 2 is a view in vertical section of the apparatus of FIGURE 1, parts being broken away.

FIGURES 3 and 4 are horizontal sectional detail views taken substantially upon the planes indicated by section lines 33 and 44- respectively of FIGURE 2.

indicated by the numeral is a vertically elongated housing which may conveniently comprise a cylindrical body of sheet metal or the like, having a closed top 12 provided with an axially disposed cylindrical upstanding collar 14- comprising an inlet opening to the housing. At its lower end the housing terminates in a conical downwardly converging lower portion 16, having at its open lower end a connector 13 by means of which a hot air supply duct 20 communicates with the interior of the housing. Indicated generally by the numeral 22 is any conventional form of heating means whereby air supplied by a blower 24 driven by a motor 26 may be heated for passage through the duct 20 and connector 18 at the lower end of the housing 10, this heated air after passing through the housing emerging through the inlet opening 14 at the upper end thereof for discharge to the atmosphere.

The housing is supported in an erect position by a plurality of legs 28.

The upper portion of the housing 10 is formed preferably of an imperforate corrugated sheet material as shown at 30 while the central portion is of sheet material atent ice as at 32, being provided with a plurality of perforations or apertures 34 for a purpose to be subsequently set forth.

Disposed adjacent the housing is a hopper 0r bin 36 into which crops or granular material of any desired character of which is desired to be dried by the apparatus may be discharged from a truck or from any other suitable source. The vertically disposed spiral conveyor 38 has its lower end disposed in a hopper 36 and its upper end is provided with a discharge duct 40 whose lower end extends into the inlet opening 14 for the discharge of granular material into the upper end of the hopper.

An electric motor 42 is operatively connected to the conveyor screw 44 disposed Within the housing of the conveyor 38 for rotation of the latter to thereby lift the granular material from the hopper to the discharge duct 40.

Disposed axially within the housing 10 and intermediate the upper and lower ends thereof is a deflector which preferably comprises a conical sheet metal member which is upwardly convergent, this member having perforations as at 52 uniformly spaced across its entire surface. The lower portion of this deflector has a cylindrical skirt or sleeve 54 dependent therefrom and likewise apertured, and radially extending webs or lugs or brackets 56 serve to rigidly secure this sleeve from the perforated portion 32 of the housing to thereby provide a peripheral or annular passageway 58 therebetween. The previously mentioned perforations 34 of the portion 32 extend into and communicate with this passageway.

A collector 60 in the form of a conical sheet metal plate having uniformly spaced apertures 62 throughout the area of the same with its upper edge fixedly secured in any suitable manner to the upper portion of the conical section 16 of the housing, and with its apex having an opening 64 therein to which is connected the upper end of a discharge chute 66 whose lower end passes through the portion 16 as at 68 and discharges into the hopper 36. At the junction of the chute 66 with the collector 60 there is provided a slide valve in the form of a fiat plate '70 having a valve port 72 therein which is adapted to be placed in registry with the opening 64 and with the upper end of the chute 66. This valve plate includes at its opposite end a pair of flanges each designated by the numeral 74 and by means of which the valve plate may be manually shifted to thereby control the discharge opening from the exterior of the housing.

From the foregoing, the operation of the device will now be understood as follows: When granular material of any desired character such as a grain crop or the like is supplied to the hopper 36, and the elevator or screw conveyor 38 is operated, the same will be lifted and discharged into the inlet opening 14 at the top of the drier. At the same time, heated air Will be supplied by the blower to a duct 20 at the bottom of the drier. The granular material will descend by gravity under free fall from the opening 14 down upon the deflector 50, will then pass radially outwardly along the sides of the same and be discharged through the peripheral passage 58 at the upper peripheral edge of the collector 60. From the latter the granular material will be collected and will be discharged through the central opening 64 and chute 66 into the hopper 36. During this free fall, the granular material will be penetrated by and subjected to the drying action of the heated air. The latter, first passing through the apertures 62 in the collector 60 will be delivered at uniform density throughout the granular material, and then will pass upwardly from the lower compartment disposed below the deflector 50, about and through the latter into the upper compartment above the deflector and thence be discharged to the atmosphere through the inlet opening 14.

During its passage through the dryer, the heated air will thus thoroughly intermingle with and pass through the falling granular material below the deflector and above the collector 60; and thereafter will again pass through the falling granular material in the upper chamber between the deflector 50 andthe inlet opening 14. The heated air thus passes through the falling grain in two stages so that the latter will be twice subjected to passage of heated air therethrough for thoroughly drying the same.

The apertures 34 in the cylindrical portion 32 of the housing serve to discharge a portion of the heated air to the exterior of the apparatus.

By manipulating the control valve 70 the rate at which the falling granular material is discharged from the device can be regulated thereby controlling the duration of time during which the granular material is subjected to the drying effects of the heated air.

Further, the conveyor 38 permits the granular material to be circulated any desired number of times through the apparatus to thus vary the effectiveness of the heating action upon the same.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A crop dryer comprising a vertically elongated housing comprising the outer wall of said dryer having a cylindrical body which is imperforate in its upper portion and is perforated uniformly over its area upon its lower portion, respectively upwardly and downwardly convergent conical top and bottom walls on said body with inlet and discharge openings therein respectively, a conical downwardly convergent collector in said housing extending entirely thereacross and having its upper portion seated in said downwardly convergent bottom wall, said collector being shallower than said bottom wall and spaced from the latter, said collector having perforations therethrough throughout its entire area for passage of air therethrough, a hopper outside of said housing, means for educting material from said collector and through said discharge opening into said hopper, means for lifting material from said hopper and discharging it into said inlet opening, means exterior to said housing for supplying heated air into said housing through said bottom wall and below and across the entire undersurface of said collector, means for distributing said heated air uniformly across said housing and through the material passing through said housing by gravity from said inlet opening, and means in said housing above said collector for slowing the fall of material and distributing the latter uniformly across said housing during the gravity fall of the material, the last-named means comprising a conical, downwardly divergent deflector having its upper portion extending into the imperforate upper portion of said body and spaced below said top wall for providing a first free fall area to be upwardly traversed by the heated air, said deflector being perforated throughout its area and including a cylindrical lower portion spaced concentrically from the perforated lower portion of the body and defining in conjunction therewith an annular second free falling area to be radially traversed by the heated air.

2. The combination of claim 1 wherein said educting means comprises a conduit comunicating with the bottom of said collector for gravity flow of material therefrom and extending through said bottom Wall for contact with the heated air introduced thereinto and a valve at the junction of the conduit with the collector for regulating the How of the material.

3. The combination of claim 2 wherein said valve includes an elongated fiat plate slidably' mounted between the collector and the conduit and projecting in opposite directions therefrom and having an opening therein for registry therewith.

4. The combination of claim 3 wherein said plate extends slidably through opposite wall portions of said bottom wall and terminate in downturned end portions providing means for manually actuating the valve from the exterior of the housing and on opposite sides thereof.

References Cited in the file of this patent UNITED STATES PATENTS 1,34l,676 Robert June 1, 1920 1,554,854 Hubmann Sept. 22, 1925 2,245,664 Gronert June 17, 1941 2,627,670 Hurst Feb. 10, 1953 2,685,343 Permann Aug. 3, 1954 2,766,534 Schaub et a1 Oct. 16, 1956 2,799,947 Elwess July 23, 1957 FOREIGN PATENTS 11,946 Great Britain of 1893 849,830 Germany Sept. 18, 1952 784,861 Great Britain Oct. 16, 1957 

